Envy's and mercy's natural genus appearnces

q. 24. 4

On the contrary, Augustine says (De Civ. Dei ix, 5) that "pity is a kind of virtue." Moreover, the Philosopher says (Ethic. ii, 7) that modesty is a praiseworthy passion. Therefore some passions are good or evil according to their species.
I answer that, We ought, seemingly, to apply to passions what has been said in regard to acts (18, 5,6; 20, 1)--viz. that the species of a passion, as the species of an act, can be considered from two points of view. First, according to its natural genus; and thus moral good and evil have no connection with the species of an act or passion. Secondly, according to its moral genus, inasmuch as it is voluntary and controlled by reason. In this way moral good and evil can belong to the species of a passion, in so far as the object to which a passion tends, is, of itself, in harmony or in discord with reason: as is clear in the case of "shame" which is base fear; and of "envy" which is sorrow for another's good: for thus passions belong to the same species as the external act.
Reply to Objection 1. This argument considers the passions in their natural